CVE-2026-61570 MPXJ: XXE Vulnerability in MerlinReader
An attacker can exploit an XXE vulnerability in MPXJ to read arbitrary local files via a crafted Merlin project database.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-61570?
CVE-2026-61570 is a high-severity vulnerability in joniles mpxj, published on 22 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
MPXJ is an open source library to read and write project plans from a variety of file formats and databases. From 5.5.5 until 16.4.1, MerlinReader creates a DocumentBuilder with default settings while parsing XML from the ZTIMEINTERVALS column of a Merlin project SQLite database, leaving doctype declarations and external entities enabled. A crafted database can cause the parser to read an arbitrary local file, although MPXJ's subsequent handling of the parsed XML makes disclosure of the file contents unlikely. This issue is fixed in version 16.4.1.
Weakness: CWE-611
Which versions are affected by CVE-2026-61570?
15 open source packages ship an affected version, including mpxj, net.sf.mpxj:mpxj and MPXJ.Net.
| Package | Affected | Fixed in |
|---|---|---|
mpxj PyPI | From 5.5.5 | 16.4.1 |
mpxj PyPI | From 5.5.5 | 16.4.1 |
mpxj PyPI | From 5.5.5 | 16.4.1 |
mpxj RubyGems | From 5.5.5 | 16.4.1 |
mpxj RubyGems | From 5.5.5 | 16.4.1 |
net.sf.mpxj:mpxj Maven | From 5.5.5 | 16.4.1 |
9 more packages
net.sf.mpxj:mpxj Maven | From 5.5.5 | 16.4.1 |
MPXJ.Net NuGet | From 5.5.5 | 16.4.1 |
MPXJ.Net NuGet | From 5.5.5 | 16.4.1 |
net.sf.mpxj NuGet | From 5.5.5 | 16.4.1 |
net.sf.mpxj NuGet | From 5.5.5 | 16.4.1 |
net.sf.mpxj-for-csharp NuGet | From 5.5.5 | 16.4.1 |
net.sf.mpxj-for-csharp NuGet | From 5.5.5 | 16.4.1 |
net.sf.mpxj-for-vb NuGet | From 5.5.5 | 16.4.1 |
net.sf.mpxj-for-vb NuGet | From 5.5.5 | 16.4.1 |
How do I fix CVE-2026-61570?
Upgrade mpxj to 16.4.1 or later.
Is CVE-2026-61570 being exploited?
There is no known exploitation of CVE-2026-61570 in the wild and no public exploit code.
Sources
Also known as GHSA-5vvx-3h34-f3gj, PYSEC-2026-4107.